Radio frequency identification (RFID) devices have emerged as an attractive approach for a variety of tracking applications. These devices, also referred to as “tags” or “labels,” are typically affixed to objects for identifying and tracking of such objects. A RFID tag is scanned or “interrogated” using radio frequency electromagnetic waves, which permit non-line of sight communication with a RFID reader. RFID tags include circuitry that can be either active or passive. When a passive RFID tag is within range of the RFID reader, the antenna of the tag receives energy from the broadcast signals of the reader. However, the transmissions are confined to a relatively short range within a physical facility or localized site. Consequently, RFID applications have been developed for site specific usage, with little or no capability to coordinate across multiple sites.
Therefore, there is a need for an approach that permits greater application of RFID technology, without the constraint of distance.